A company’s board of directors is supposed to act in the best interests of shareholders, but that doesn’t always seem to be the case in Silicon Valley, where some chief executives are capable of driving boards to act in their own interests.

Zuckerberg seems to have had an ace in the hole, though: board member and venture capitalist Marc Andreessen. Documents in the lawsuit showed texts in which Andreessen was advising Zuckerberg and helping him prepare for questions from a Facebook special committee of the board that reviewed the three-way stock split. Andreessen, one of the three members of that committee, even coached Zuckerberg via text message during one board call.

“Facebook is confident that the special committee engaged in a thorough and fair process to negotiate a proposal in the best interests of Facebook and its shareholders,” Facebook said in an emailed statement.

Zuckerberg is also chairman of the board, which counts Chief Operating Officer Sheryl Sandberg and Jan Koum — co-founder and CEO of WhatsApp, an app that Zuckerberg acquired for $16 billion plus incentives — among its members in addition to Andreessen. Together, that group makes up exactly half of the eight-member board, a voting bloc that could ensure Zuckerberg gets his way.

Musk had a number of conflicts of interest in the deal for SolarCity, a solar installer for which he was the principal investor, chairman and cousin of the two founders who act as its top executives. A strong, independent board would have had some serious questions about the deal and how it could be in Musk’s favor while possibly not in Tesla’s, and Musk rightly recused himself from board discussions.

Musk — also chairman at Tesla — had no need to worry that the board would decide in his favor, though, considering how many had a vested interest in seeing SolarCity propped up by a larger entity. Tesla board members included Antonio Gracias, who was also a SolarCity board member; Brad Buss, the former chief financial officer for SolarCity; and Steve Jurvetson, whose venture-capital firm invested in SolarCity. Another Tesla board member is Elon Musk’s brother, Kimbal Musk.

In its recommendation against voting for the deal, Glass Lewis cited the board’s review, saying it was “hastily managed by a board room rife with conflicts and seemingly limited interest in moderating the apparently ardent strategic and financial preferences” of Elon Musk.

Forward-thinking executives like Zuckerberg and Musk draw investors to Silicon Valley companies, but building a new “old-boy network” through their boards could also drive them away. Instead of doing what they want and paying off those who dissent through shareholder lawsuits, tech companies’ founders and top executives should start actually constructing boards to do what they are supposed to do.

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